The present invention relates to a video camera unit and more particularly to a compact and bright video camera unit.
Recently, a very compact 1/3 inch solid-state image pick-up device has been developed and a door scope TV camera, etc. has been experimentally manufactured as its application.
A wide lens used therein is constructed by combining 8 to 10 lenses since it should have certain optical property relative to spherical aberration, astigmatism, distortion aberration, chromatic aberration, sine condition, etc. as disclosed in e.g. JP-A-48-64927. Further, a solid state image pick-up chip (IC chip) constructed by combining a photodiode and a switch MOS FET is disclosed in e.g. JP-A-56-152382. And in the television camera for monitoring, family use, etc., an optical lens used therein is provided with an automatic diaphragm or stop mechanism.
However, the above wide angle lens, which is constructed by many lenses, is not suitable to miniturizing.
Also, the above lens provided with an automatic diaphragm mechanism requires relatively complicated mechanical components and so makes the lens portion in the television camera bulky and requires high production cost therefor. Further, the automatic diaphragm mechanism, which is constructed by relatively complicated mechanical components, is problematic in its reliability due to possible aberration of the mechanical components.
U.S. patent application Ser. No. 102649 (filed Sep. 30, 1987) discloses an image sensor with variable sensitivity.